Originally Posted by bigmatt

I did email mark at massive mods, he thinks it's a tight engine. it works fine. no over heating no erratic idle nothing of the sort,If any thing I would say that it was tighter then my other 7 port. I have pretty much chewed up the fly wheel getting it unstuck. so I think I will keep using the mmmods run in oil in 1 more tank of fuel and take it slow on the break in. but I know I read some where the same problem and that ended in a broken rod and crank pin. and I am trying to remember but I think with the engine being so tight the census was he should have used the heat gun to warm up every time during break in. If I remember right.